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Engine Swap - Simple Question (I Hope)


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I'm going to swap in a fresher engine temporarily while I do a few other repairs/refurbishments.

 

My set-up 1987 4L w/BA-10/5.

 

The replacement 1987 4L previously mated to an AT.

 

Is there anything I need to do/retain/source to fit the engine from an AT equipped flywheel to a manual trans? Seems that once all the AT components are removed, then the flywheels should be identical. But IDK for sure. :???:

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The auto should have a flex plate , the starter gears will be on the torque converter .

 

Just remove all the auto-stuff from the rear of the new engine , bolt on your pressure plate , and then clutch assembly , drop 'er in

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The auto should have a flex plate , the starter gears will be on the torque converter .

 

Just remove all the auto-stuff from the rear of the new engine , bolt on your pressure plate , and then clutch assembly , drop 'er in

 

 

Thanks, but do you mean bolt on the flywheel? If not, then I'm confused.

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The auto should have a flex plate , the starter gears will be on the torque converter .

 

Just remove all the auto-stuff from the rear of the new engine , bolt on your pressure plate , and then clutch assembly , drop 'er in

 

Starter gear teeth are on the flex plate.

 

The flex plate will face to be swapped in place of the flywheel.

 

You will have to purchase a new pilot bushing (input bearing) for your year truck, and install it. there is no re using a pilot bushing...you destroy then to remove them.

 

Once that is done, install the clutch and pressure plate.

 

Hope that helps. New pilot bushing is under $ 10 btw

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Here's your clutch and standard gear , sorry , didn't mean to sound confusing .

 

 

You'll see this takes the place of the flex plate and trorque converter on the manuals . The starter teeth are on the flywheel , as well as the notches for the crank sensor . What you see is all you need on the back of the engine .

 

Not going against the idea of a new pilot bearing( I call them throw-out bearings , pilot is correct though) , but if you can't hear it , don't bother . Do it when you have your engine work complete and go to reinstall it .

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...Umm...no

 

The throw out bearing is the throw out bearing. It pages the fingers on the pressure plate, which allows the clutch to disengage.

 

The pilot bushing is located I the crankshaft and keeps the input shaft and clutch disk aligned to the crank shaft ... The new engine does not have one, and it is NECESSARY or you will destroy your transmission.

 

Beyond that, three throw out its part of his slave cylinder.

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...Umm...no

 

 

The pilot bushing is located I the crankshaft and keeps the input shaft and clutch disk aligned to the crank shaft ... The new engine does not have one, and it is NECESSARY or you will destroy your transmission.

 

 

pilot bearing goes in the flex plate , at least it did on mine(2.5) Look at the pic . Had them install it when it was resurfaced

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Thanks for all the input.

 

My understanding of the differences are:

 

The engine fitted to a manual trans terminates with the flywheel, which has the ring gear on its circumference and a pilot bushing in the center to accept the nose of the mainshaft and keep things aligned. The clutch disk/pressure plate bolt to the flywheel, and the throwout bearing/slave cylinder (in the concentric version) attach to the trans.

 

The engine fitted to an auto transmission terminates with a flexplate/ring gear which mounts the torque converter. So if I remove the flex plate assy, and replace it with my existing flywheel assy and a new pilot bushing, mount the disk/pressure plate, then I'm good.

 

BTW the main reason for all of this is that the replacement throwout bearing/slave cylinder that I installed less than three months ago (from a NAPA clutch pack kit) has already crapped the bed. Rather that pull the trans/tc one more time (and do all the work by crawling around under the truck), and end up no better off than I thought I was three months ago, I want to work from the top, run a fresher engine (and thus actually IMPROVE things), while I use the original block as the basis for some kind of stroker.

 

BTW one more question: Any thoughts on whether I can pull the engine without dismounting the hood. I don't mind removing it, but remounting/realigning it can be a PITA.

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You can do it without removing the hood, but you'll probably have to pull it back further than the prop rod can hold it up. When I yanked the motor out of my first XJ, I kept the hood back with ratchet straps hooked to the roof rack.

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Remove the hood via the 4 bolts on the hinge . You could even trace it out with a felt marker , but , I just used the obvious mark left from it being bolted on . I'm not even certain there is any adjustment on these 4 bolts

 

I did that when I did my conversion from the 98 XJ , took the hood off the XJ from the hinge/firewall . Bolted it on , and closed the hood . Lined up perfectly . never adjusted it first or last .

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You can do it without removing the hood, but you'll probably have to pull it back further than the prop rod can hold it up. When I yanked the motor out of my first XJ, I kept the hood back with ratchet straps hooked to the roof rack.

 

 

Thanks.

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Remove the front clip instead. Easier to align by yourself than the hood.

 

Agreed, pull the header panel and the radiator out of the way, if you have AC you can unbolt the compressor and then rotate the ac condensor out of the way towards the right of the vehicle, this way the AC system doesn't get discharged and you pull the engine and tranny together right out over the front lower radiator support.

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Remove the front clip instead. Easier to align by yourself than the hood.

 

Pilot bushing is in the crankshaft on the 4.0. It will be a .750 ID bearing...not sure on the OD

 

This is an 87 we're talking about. The .75 was introduced in 92.

 

The ID should be a tad over 1/2 inch. Not sure exactly, there seem to be a wide variety of measurements depending on what brand you buy.

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I pulled my motor, with clutch, and only removed the upper radiator support/tiebar and radiator, mechanical fan, and MAP sensor. (Just barely though!) And my trans/t-case/ crossmember were already out the bottom. (Don't know what kind of difference that'll make)

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It's quite a bit different when the trans is already out.

 

Maybe not for pulling, but when it goes back in, you're going to want as much wiggle room as you can get. Lining up the input shaft on the trans isn't the funnest thing.

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Another bit of advice to the OP.

 

Remove your CPS before you pull the motor, and put the motor back in before you re-install your CPS.

I realize dealing with the CPS on a 4.0 is a PITA, but doing this is much better than having to replace it after you're "done". Doing the CPS with the manifolds out of the way isn't that bad.

 

It is very easy to break during removal/installation, and you probably won't notice until the truck doesn't start.

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